As disclosed in U.S. Patent Application Publication No. 2011/0030276, there is known a sliding window equipped with a defroster for removing frost by a printed heating wire, which is attached to a rear window of a vehicle. In such a sliding window, a band-shaped flexible cable is used in order to supply electric power to the heating wire regardless of the opening and closing state of the sliding window.
However, since the flexible cable is curved in a circular-arc shape, a fixing mechanism and a holding mechanism are required. Thus, a power supply apparatus which supplies electric power to an electrical equipment such as the heating wire of the sliding window, tends to be complex. When the power supply apparatus has a complex structure, for example, a technical difficulty occurs in a vehicle layout such that the power supply apparatus may not be easily provided between the rear panel and the trim board.